When Apple announced new iMacs last month, it included a major step forward amid the subtle-but-welcome refinements in most of the models: the first ever iMac to offer a quad-core processor. The new high-end 27-inch iMacs are the first to use Intel’s Core i5 and Core i7 quad-core processors, and they were not available at the time of the announcement. But finally, the wait is over, and the Core i5 and Core i7 27-inch iMacs have arrived—and let me tell you, it was worth the wait.

http://www.macworld.com/article/143970/2009/11/core15_imac.html?t=201